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<TITLE>80386 Programmer's Reference Manual -- Opcode AND</TITLE>
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<H1>AND -- Logical AND</H1>
<PRE>
Opcode    Instruction          Clocks    Description

24 ib     AND AL,imm8          2         AND immediate byte to AL
25 iw     AND AX,imm16         2         AND immediate word to AX
25 id     AND EAX,imm32        2         AND immediate dword to EAX
80 /4 ib  AND r/m8,imm8        2/7       AND immediate byte to r/m byte
81 /4 iw  AND r/m16,imm16      2/7       AND immediate word to r/m word
81 /4 id  AND r/m32,imm32      2/7       AND immediate dword to r/m dword
83 /4 ib  AND r/m16,imm8       2/7       AND sign-extended immediate byte
                                         with r/m word
83 /4 ib  AND r/m32,imm8       2/7       AND sign-extended immediate byte
                                         with r/m dword
20 /r     AND r/m8,r8          2/7       AND byte register to r/m byte
21 /r     AND r/m16,r16        2/7       AND word register to r/m word
21 /r     AND r/m32,r32        2/7       AND dword register to r/m dword
22 /r     AND r8,r/m8          2/6       AND r/m byte to byte register
23 /r     AND r16,r/m16        2/6       AND r/m word to word register
23 /r     AND r32,r/m32        2/6       AND r/m dword to dword register
</PRE>

<H2>Operation</H2>

<PRE>
DEST := DEST AND SRC;
CF := 0;
OF := 0;
</PRE>

<H2>Description</H2>

Each bit of the result of the AND instruction is a 1 if both corresponding
bits of the operands are 1; otherwise, it becomes a 0.

<H2>Flags Affected</H2>

CF := 0, OF := 0; PF, SF, and ZF as described in <A HREF="appc.htm">Appendix C</A>

<H2>Protected Mode Exceptions</H2>

#GP(0) if the result is in a nonwritable segment; #GP(0) for an illegal
memory operand effective address in the CS, DS, ES, FS, or GS segments;
#SS(0) for an illegal address in the SS segment; #PF(fault-code) for a page
fault

<H2>Real Address Mode Exceptions</H2>

Interrupt 13 if any part of the operand would lie outside of the effective
address space from 0 to 0FFFFH

<H2>Virtual 8086 Mode Exceptions</H2>

Same exceptions as in Real Address Mode; #PF(fault-code) for a page fault


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<B>up:</B> <A HREF="c17.htm">
Chapter 17 -- 80386 Instruction Set</A><BR>
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